Each sensory neuron is uniquely identified by its sensory properties. One mechanism responsible for generating the specificity and diversity of sensory cells is the regulated expression of receptors and signaling components in a cell-type specific fashion. Unlike rodents, in which only one olfactory receptor is expressed in a neuron, in C. elegans, diversity of sensory cell function is generated in part by the expression of multiple, distinct subsets of receptors in each chemosensory neuron type. Our laboratory has identified SNS-8, a homolog of the MARK/PAR-1/ SAD-1 family of serine threonine kinases, as a key component of efficient olfactory receptor expression in C. elegans. The mechanisms by which SNS-8 functions in regulating receptor expression will be examined through both genetic and genomic analyses. Since little is known about the molecular mechanisms governing expression of olfactory receptors, identifying additional genes required for SNS-8 signaling should elucidate how olfactory receptor regulation, and hence the diverse functions of the nervous system, is achieved in higher organisms, in addition to elucidating general mechanisms of gene expression.